Objective: The proposed research aims to use a life-course approach to develop a better understanding of the interplay of biological, environmental and behavioral determinants and antecedents of oral conditions from childhood to oral health by elucidating the nature, scale, persistence and potential mutability of oral health disparities in a population-based cohort of adults. Methods: The Dunedin Study has traced the development of a representative 1972 birth cohort of 1,000 New Zealand men and women at birth and ages 3, 5, 7, 9, 11, 13, 15, 18, 21 and 26. New data will be gathered at age 31, enabling analysis of oral health disparities data from childhood to age 31. The research will: (1) document the natural history of oral conditions through to the 4th decade of life; (2) examine the influence of earlier SES (and SES transitions) on adult oral health; (3) using periodontal disease as a model, test hypotheses about gene-environment interactions in the origins of poor adult oral health; and (4) determine the extent to which poor oral health is an important contributor to (a) poor physical health and (b) experience of adverse life outcomes by the 4th decade of life. The planned research will provide unique information on the scale, persistence and potential mutability of disparities in oral health through the first four decades of life, and will assist in identifying those clinical, public health and policy interventions, which are likely to be most appropriate and efficacious in reducing oral health disparities. The Dunedin Study offers a unique opportunity to conduct such an investigation because of the comprehensive data archive, which has already been assembled. Implications: The persistence of oral health disparities has not been investigated through the entire life course to date, and close examination of the degree to which the Dunedin cohort's early-life disparities in oral health persist into adulthood would be invaluable in determining whether (and to what extent) such inequalities can be reduced by clinical, public health or policy interventions. The outcome of this important work will inform and determine the nature of measures which are taken to reduce oral health disparities.